fix: truely copy _ProgramMap when RCU write

decoder/pools.go

@@ -36,10 +36,11 @@ const (
 )
 
 var (
-    stackPool    = sync.Pool{}
-    valueCache   = []unsafe.Pointer(nil)
-    fieldCache   = []*caching.FieldMap(nil)
-    programCache = caching.CreateProgramCache()
+    stackPool     = sync.Pool{}
+    valueCache    = []unsafe.Pointer(nil)
+    fieldCache    = []*caching.FieldMap(nil)
+    fieldCacheMux = sync.Mutex{}
+    programCache  = caching.CreateProgramCache()
 )
 
 type _Stack struct {
@@ -75,7 +76,9 @@ func freezeValue(v unsafe.Pointer) uintptr {
 }
 
 func freezeFields(v *caching.FieldMap) int64 {
+    fieldCacheMux.Lock()
     fieldCache = append(fieldCache, v)
+    fieldCacheMux.Unlock()
     return referenceFields(v)
 }
 

internal/caching/pcache.go

@@ -50,6 +50,18 @@ func newProgramMap() *_ProgramMap {
     }
 }
 
+func (self *_ProgramMap) copy() *_ProgramMap {
+    fork := &_ProgramMap{
+        n: self.n,
+        m: self.m,
+        b: make([]_ProgramEntry, len(self.b)),
+    }
+    for i, f := range self.b {
+        fork.b[i] = f
+    }
+    return fork
+}
+
 func (self *_ProgramMap) get(vt *rt.GoType) interface{} {
     i := self.m + 1
     p := vt.Hash & self.m
@@ -70,12 +82,12 @@ func (self *_ProgramMap) get(vt *rt.GoType) interface{} {
 }
 
 func (self *_ProgramMap) add(vt *rt.GoType, fn interface{}) *_ProgramMap {
-    p := self
+    p := self.copy()
     f := float64(atomic.LoadUint64(&p.n) + 1) / float64(p.m + 1)
 
     /* check for load factor */
     if f > _LoadFactor {
-        p = self.rehash()
+        p = p.rehash()
     }
 
     /* insert the value */

internal/caching/pcache_test.go

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2021 ByteDance Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package caching
+
+import (
+    `sync`
+    `testing`
+
+    `github.com/bytedance/sonic/internal/rt`
+)
+
+func TestPcacheRace(t *testing.T) {
+    t.Parallel()
+
+    pc := CreateProgramCache()
+    wg := sync.WaitGroup{}
+    wg.Add(2)
+    start := make(chan struct{}, 2)
+
+    go func(){
+        defer wg.Done()
+        var k = map[string]interface{}{}
+        <- start
+        for i:=0; i<100; i++ {
+            pc.Put(rt.UnpackEface(k).Type, k)
+        }
+    }()
+
+    go func(){
+        defer wg.Done()
+        var k = map[string]interface{}{}
+        <- start
+        for i:=0; i<100; i++ {
+            pc.Get(rt.UnpackEface(k).Type)
+        }
+    }()
+
+    start <- struct{}{}
+    start <- struct{}{}
+    wg.Wait()
+}

issue45_test.go

@@ -0,0 +1,90 @@
+/*
+ * Copyright 2021 ByteDance Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package sonic
+
+import (
+    `fmt`
+    `sync`
+    `testing`
+)
+
+func ExtractJson(idx int, body interface{}) {
+    j := []byte(exampleJson[idx])
+
+    // REPLACE sonic WITH json
+    err := Unmarshal(j, &body)
+    if err != nil {
+        fmt.Println(err.Error())
+        return
+    }
+}
+
+var exampleJson1 = `{}`
+
+var exampleJson2 = `{}`
+
+var exampleJson = []string{exampleJson1, exampleJson2}
+
+type raceTestStruct struct {
+    f1 *[]raceTestStruct2 `json:"f1"`
+    f2 *int               `json:"f2"`
+    f3 *string            `json:"f3"`
+    f4 *string            `json:"f4"`
+}
+type raceTestStruct2 struct {
+    g1 *string           `json:"g1"`
+    g2 *string           `json:"g2"`
+    g3 *string           `json:"g3"`
+    g4 []raceTestStruct3 `json:"g4"`
+}
+type raceTestStruct3 struct {
+    e1 *string  `json:"e1"`
+    e2 *string  `json:"e2"`
+    e3 *float64 `json:"e3"`
+    e4 *float64 `json:"e4"`
+}
+
+func TestExtracJson(t *testing.T) {
+
+    wg := sync.WaitGroup{}
+
+    resultChan := make(chan raceTestStruct, 2)
+
+    wg.Add(1)
+    go func() {
+        defer wg.Done()
+        var model raceTestStruct
+        ExtractJson(0, &model)
+        resultChan <- model
+    }()
+
+    wg.Add(1)
+    go func() {
+        defer wg.Done()
+        var model raceTestStruct
+        ExtractJson(1, &model)
+        resultChan <- model
+    }()
+
+    var results []raceTestStruct
+    for i := 0; i < 2; i++ {
+        results = append(results, <-resultChan)
+    }
+
+    wg.Wait()
+    close(resultChan)
+}